Air-compressor.



D, 0. ROYSTER.

AIR (SOIVIPRESSOR= APPLlcATloN FILED 1AN.23.1915.

1,293,904, yafented Feb, 4, 1919.

i Beitknown that I, DAVID disposed plate DAVID 0. ROYSTER, OF 1ST. LOUIS, MISSOURI.

AIR-COMPRESSOR.

Specication of Letters Patent.

Patented Feb. 4, 1919.

i Application filed January 23, 1915. Serial No.` 3,878.

To all 'whom t may concern:

O. Rorsrnn, a citizenofthe lUnited States, residing at St. Louis, State of Missouri, have invented certainnew "and useful Improvements in Air- Compressors, of which the following is a specification. j j

My-invention relates to new and useful improvements in air compressors of that type which `employs two or 'more cylinders and being electrically driven.

' The principal objects of my invention are, first to provide an air compressor which is composed of comparatively few parts, therebj1-materially reducing the liability` of the device getting out of order; to provide a pump which can becheaply manufactured and economically operated; to combine with the pump a small electric motor.; to provide simple automatically operating means which is controlledby the pressure produced by the pump for cutting out the motorr;` and furtherto provide simple means for effecting a lubrication of the pistons.

With the foregoing and other objects in view, my invention consists in certain novel features of construction and arrangement ofparts, hereinafter more fully described, claimed and 'Shown' in the accompanying drawings, in which@ Y Figure 1 is a side elevational View of a compressor of my improved construction with parts thereof in vertical section.

Fig. 2 is a front-elevational view of the compressor.

Fig. 3 is a vertical section taken through the center of the check valves which control the inlet and outlet of air to and from the cylinders. j i l Fig. 4 isa vertical section of one of the pistons and showing the means utilized for delivering oil to the surface thereof.

l Referring by numerals to the accompanying drawings, 1 designates a plate, preferably of cast metal, and formed p integral therewith'is a series of depending posts 2, the lower 'ends of which carry a horizontally 3, the same being adapted to be attached to 4an air tank or reservoir 4.

Formed integral with vand projecting up- .wardly from plate 1 is a standard 5, the

same lbeing provided at its upper end with a vhorizontally disposed bearin 6 in which is mounted for rotation a sha t 7. Fixed on one end of this shaft is a gear wheel 8 and fixed on the opposite endthereof is a disk 9. Formed integral with the plate 1 near the ends thereof are vertically disposed cylinders 10, open at their upper ends, and mounted for operation in said cylinders pistons 11, same being provided with suitable packing rings 12. These pistons are provided with pockets 13 in their upper portion-s,`which pockets are adapted to contain oil and positioned transversely in each piston is a pin 14 in the end portions of which are formed passage Y ways 15 which establish communication from the pocket 13 to the externall surface of the piston, thereby permitting oil to flow from said pocket to the bearing surface of the piston.

Loosely mounted on the central portions of the pins 15 are connecting rods 16, the upper ends of which are journaled onjwrist pins 17, which latter are carried by gear wheel 8 and disk 9. j Mounted on plate 1 is a small motor 18, the shaft of which is provided with a pinion 19 which meshes with the teeth of gear wheel 8. An ordinary electric switch 20 is fixed on a part of the standard 5 and said switch is connected to the lines leading to the motor.

The means of automatically operating this switch and which is controlled by the pressure created by the pump comprises a housing 21 which is located on plate 1 and positioned in said housing is a fiexible diaphragm 22. Positioned on top of said diaphragm. is a plate 23 carrying an upwardly projecting pin 24 which operates through the upper portion of housing` 21 and located on the upper portion of said pin is a compression spring 25. The upper end of this spring bears against the lower end of a cylindrical nut 26 the same being screwseated in the upper end of'housing 21 and which nut when manipulated increases or decreasestension offered by the spring.

The upper end ofl pin 23 is pivotally connected Ito a lever 27, the same being fulcrumed at 28 to the upright 5 and the opposite end of said lever being bifurcated to form a pair of ngers 29 which straddle the switch 20and are adapted to engage the Vpush pins thereof.

. connection is made when it is desired to Vwardly through plate use the compressed air. l

Connected to pipe 35 and leading up- 1 is a pipe 37 to which is connected a gage 38 by means of which the pressure of the air being used can be end of one of the cylinders readily ascertained.

The check valves for controlling the inlet and outlet of air to and from the cylinders 10 are each formed with a short vertically disposed cylindrical body 39 from the lower end of which projects a tubular extension 40, the same being screw-seated in the lower 10. Formed in this housing 39 is a valve seat 41 on top of which operates a check valve 42.

The upper end of housing 39 is closed by a screw plug 43 and leading from the chamber within housing 39y above valve 42 is a tubular nipple 44 to which is connected the upper end of a tube 45, which latter leads downwardly and is connected to tank 4.

Screw seated in the lower end of housing 39 is the upper end of a tubular elbow 46,

the same being provided at its upper end with a valve seat 47 on top of which is positioned a check valve 48.

The air drawn to the cylinder 10 enters through tubular elbow 46 and passes check valve 48 as it enters chamber within housing 39.

The operation of my improved compressor is as follows:

Current supplied to motor 18 enters same and pinion 19 engaging with gear wheel 8 drives shaft 7. lThe rods 16 are connected to gear wheel 8 and disk 9 and by reason of such connection pistons 11 are reciprocated within cylinders 10.

On the up-stroke of the piston air is drawn in through corresponding tubular elbow 46, past inlet check valve 48 through tubular connection 4() into the lower portion of cylinder 10.

On the down-stroke of the piston the air thus drawn into cylinder is forced out through tubular connection 4Q, past check valve 42, from thence through tubular connection 44 and tube 45 into tank 4. Nut 26 is manipulated to regulate the tension of spring 25, thus controlling the degree of pressure required to raise diaphragm 22, and when the pressure within tank 4 eX- ceeds the maximum point for vwhich the regulator is set, diaphragm 22 will be forced upwardly, thereby forcing upward plate 23 and pin 24, and consequently swinging lever 27 on its fulcrum. This action shifts the position of fingers 29 and throws switch 20,

thereby cutting off current to motor 18 andand tubular elbow 46 may be readily removed to adjust or renew check valves 42 and 48.

It will be understood that when pressure in tank 4 lowers sufficiently to permit spring 25 to move diaphragm 22 downward lever 27 will be actuated tothrow in switch 20, thereby supplying the motor with current and automatically starting the pump.

lf desired, a housing either wholly or partially transparent may be positioned on plate 41 over the operating mechanism positioned on said plate, andwhich housing; is shown in dotted lines in Fig. 2.

An air compressor of myf'improved c onstruction is lcomparatively simple, can be easily and cheaply manufactured, will not readily get out of order, is economical in pointof power used in operation, andthe operation of said compressor vis entirely automatic and controlled by the Vdegree of pressure pumped up within the cylinder or container to which said compressor connected.

It will be readily understood that minor changes in the size, form and construction.

of the various parts of my improved compressor can be made and substituted for those herein shown and described, without departing from the spirit of my invention,

the scope of which is set forth in the apl pended claim.

I claim:

The combination with a reservoir of a member adapted to be directly connected to said reservoir, posts projecting upwardly from said member, a plate carried by said posts, a pair of cylinders formed integral with said plate, said cylinders being spaced apart and'projecting above and below the plate, a bracket integral with said plate and projecting upwardly therefrom between the cylinders, a bearing formed in the upper end of said bracket, a shaft journaled in the said bearing, a gear wheel on one end of said shaft, a disk on the other end of said pistons operating within the cylinders, piston rods connected to said pistons and the gearl wheel and disk, an electric motor mounted on the plate'to one side of `the shaft,

bracket, a pinion carried by the motor shaft, In testimony whereof I hereunto afix my which pinion meshes with the gear Wheel, a. signature. in the presence of two Witnesses, separate inlet and outlet check valve for this 21st day of January, 1915. controlling the passage of air to and from DAVID O. ROYSTER. each cylinder, and a. connection from each Witnesses: outlet check valve to the receptacle to which M. P. SMITH, the compressor is applied. WM. JANUS.

Copies of this patent may be obtained for ve cents each, by addressing the Commissioner of Patents, Washington, D. 6. 

